A and B can do a piece of work in 21 and 24 days respectively.They start the work together and after some days, A leaves and B completes the rest of the task in 9 days. After how many days did A leave?
A.
8
B.
7
C.
6
D.
5
Answer: Option B
Explanation:
Part of work completed by A in a day = 1/21 Part of work completed by B in a day = 1/24 Part of work completed by them together in a day = (1/21)+(1/24) = 5/56 Part of work completed by B in 9 days = 9/24 = 3/8 If A left after x days, (5x/56)+(3/8) = 1 x = 7
A,B,C, can do a work in 8,14,16 days respectively. A does the work for the first 2 days. B continues from it and finishes 2/3rd of the remaining work. C finishes the remaining work. How many days would have taken to complete the work?
A.
11
B.
12
C.
13
D.
14
Answer: Option C
Explanation:
A completes 2*(1/8) = 1/4th of the work 2/3rd of the remaining work = (3/4) * (2/3) = 1/2 B completes 1/2 of the work in (1/2)÷(1/14) = 7 days C completes 1/4th of the work in (1/4)÷(1/16) = 4 days They take 13 days to complete the work
If 6 men working together can complete 50 identical tasks in 4 hours then how many such identical tasks can be completed if 10 men are working together for 6 hours?
A.
20
B.
25
C.
125
D.
160
Answer: Option C
Explanation:
M1*D1*W2 = M2*D2*W1 Where, M – number of people working D – time of work W – number of tasks or work 6*4*W2 = 10*6*50 W2 = 125 tasks